Analysis of the F508 mutation in a Brazilian cystic fibrosis population: comparison of pulmonary status of homozygotes with other patients

RESUMO

Sixty-one cystic fibrosis patients admitted for check-up or antibiotic tretment were enrolled for genetic and clinical evaluation. Genetic analysis was performed on blood samples stored on neonatal screening cards using PCR techniques to determine the presence of deltaF508 mutations. Clinical evaluation included Shwachman and Chrispin-Norman scores, age at onset of symptoms and diagnosis, spirometry, awake and sleep pulse oximetry, hyponychial angle measurement and presence of chronic Pseudomonas aeruginosa colonization. Eighteen patients (29.5 percent) were homozygous for the deltaF508 mutation, 26 (42.6 percent) had one deltaF508 mutation and 17 (27.9 percent) were noncarriers, corresponding to a 50.8 percent prevalence of the mutation in the whole population. Analysis by the Kruskal-Wallis test for comparison of genetic status with continuous variables or by the chi-square test and logistic regression for dichotomous variables showed no significant differences between any two groups for alpha=0.05. We conclude that genetic status in relation to the deltaF508 mutation is not associated with pulomnary status as evaluated by the above variables.